Final answer:
d) IgG. The correct immunoglobulin that can initiate the classical pathway of complement is IgG.
Step-by-step explanation:
The correct answer is d) IgG.
The classical pathway of complement is initiated by the binding of IgG antibodies to their target antigens. This binding triggers a cascade of reactions that ultimately leads to the destruction of the target cell.
IgG is the most abundant antibody in the bloodstream and is involved in long-term immunity against many pathogens.